♦ In areas where shale-drilling/hydraulic fracturing is heavy, a dense web of roads, pipelines and well pads turn continuous forests and grasslands into fragmented islands. Photo: Flickr.com / Simon Fraser University - University Communications
Fracking has altered the global geopolitics of energy – probably for the better. North America is nearly independent of imported oil and is starting to export gas. It is therefore no surprise that the costs, benefits and risks are being hotly debated in South Africa.
Less than five years ago there was talk that the US had hit peak oil. This meant that it would soon be so beholden to the Middle East for oil that the US dollar would plummet in value because the US balance of trade would be so adverse.
As a consequence of oil and gas production from fracking, the US now has almost enough oil to be fully fuel independent. Other local energy supplies, such as coal, have also been replaced. There are a number of examples in the US where this has happened. About 60GW of coal-fired generation will be closed by 2020.
But the process of fracturing rock by hydraulic pressure to uncover oil or gas carries risks. There are many fears about what could go wrong in fracking. Because of its high-pressure operations, the biggest fears relate to leaks and the consequences of leaks.
Does fracking present a potential solution to South Africa’s energy crisis? Or are the risks too high?
About 75% of South Africa’s energy supply comes from coal. This is very high and only a few countries in the world are this heavilydependent on coal. At present 94% of South Africa’s energy needs come from coal and oil. One-fifth of the country’s energy needs are met by oil. And gas makes up less than 1% of its needs. Renewable energy is starting to make a contribution, with the Department of Energy focusing on biomass, wind and solar energy.
Potential problems and some answers
In North America more than one million holes have been hydraulically stimulated, the technical term for fracking. There is only one documented case of a leak of fracking fluids. This happened when the drillers tried to pressurise a hole unaware of the existence of another hole close-by. They spotted their own fluid coming up from the ground and immediately stopped operations. The leak had minimal impact. Fugitive emissions from fracking operations are also a cause for concern because they could contribute to global warming. Methane has 25 times greater greenhouse effect than carbon dioxide.
But evidence shows that there is less than 1% of the production of gas from fracking in the US. The impact is considered to be small. In the US about 100 times the quantity of gas is lost naturally from wetlands.
There is also the problem of what to do with the water that is ejected when the gas or oil starts to flow. It contains chemicals, sand and mud from the drilling. In the US waste water is being treated using normal water purification techniques. It can be treated by normal water purification techniques, and cheaply restored to agricultural level. However, producing drinkable water is more expensive.
There are also fears about the toxicity of the chemicals used in fracking. These arose because at the outset of the industry the composition of the additives was a closely held secret. However, additives are now the subject of commercial supply and sellers disclose the composition. Recently, the US Environmental Protection Agency has passed legislation requiring full disclosure.
Fracking does cause environmental damage. The Environmental Protection Agency has recently released a report on fracking and its impact on water. It is open for public comment and peer-review. There have been illegal discharges into streams and municipal sewerage works. But most has been the result of poor handling of water expelled from the well.
In North America a lot of fracking has been done by small companies, known as wildcatters, that engage in speculative drilling. They arereluctant to spend much on cleaning up the water. Gas majors, such as Shell and BP, are very concerned about their reputation and have, in general, been much more responsible in their handling of the waste water.
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